Improvement in telegraph-insulators



J. H. BLOOMPIELD. Telegraph-Insulator.

Patented June 3,1879.

w ww ATTORNEYSE m w U WWW/M W w w UNITED STATES PATENT OFFICE.

JOHN H. BLOOMFIELD, OF GONOORDIA, ENTBE RIOS, ARGENTINE REPUBLIC.

IMPROVEMENT lN TELEGRAPH-INSULATORS.

Specification forming part of Letters Patent No. 216,138, dated June I), 1379; application filed January 29, 1879.

To all whom it may concern:

Be it known that I, JOHN HENRY BLooM- FIELD, of Concordia, Entre Rios, in the Republie of Argentine, have invented a new and useful Improvement in Insulators for Telegraph-Wires, of which the following is aspecification.

Figure 1 is a side view of one of my improved insulators. Fig. 2 is a longitudinal section otthe same.

Similar letters of reference indicate corresponding parts.

The object of this invention is to furnish improved insulators for telegraph-wires which shall be simple in construction, easily applied and replaced, which will not be liable to be broken by the breaking of the wire, which will not allow the wire to run down or slacken for several poles when the wire breaks, and which will not be liable to have the insulation of the wire destroyed by birds building nests of mud around them.

The invention consists in an insulator for telegraph-wires, formed of the insulator made of glass, porcelain, or glazed brown ware, perforated longitudinally and countersunk at the lower end of the peribration, the screw made with a round head having a square hole formed in it, the rubber bands, and the rubber rings, as hereinafter fully described.

A reprcsentsthe insulator, which is designed to be made of glass, porcelain, or glazed brown ware, with a convexcd upper end, a concaved lower end, and a downwardly-proiecting cupflange around its upper part covering the part around which the wire is to be fastened. The insulator A is perforated lou gitudin all y to receive the screw B, by which it is secured to the lower side of the cross-bar (J, attached to a pole.

The pertoration is made a little larger than the body of the screw B, so that the insulator cannot be broken by the expansion of the said screw.

The lower end of the perforation through the insulator is countersunk to receive the head of the screw B, and the said head has a square hole or cavity formed in it, in line with the axis of the screw, to receive a key for screwing it into and out of the crossbar 0.

Upon the body of the screw 13, within the upper and lower parts of the perforation through the insulator, are placed two rubber bands, 1), to fill up the space between the screw and insulator and keep the said insulator firm and steady.

Upon the body of the screw B, at its head, is placed a rubber ring, E, which is made a little smaller than the said head, and which, when the screw is turned up into place, is pressed into the countersink in the insulator A, and around the outer edge of the said screwhead, so as to cushion the said screw-head and keep it from coming in contact with the said insulator.

Upon the screw B at the upper end of the insulator A is placed a rubber ring, E, which, when the said screw is turned up into place, is pressed into the upper end of the space between the screw and insulator, and between the insulator and the cross-bar 0, so as to cushion the said insulator to the said cross-bar.

By this construction the insulator A iskept from contact with the screw B and the crossbar 0, and the said screw is allowed to expand without breaking the insulator A, and to contract withouL loosening it.

The under side of the cross-bar O is conca ved to receive the upper end of the insulator A, to protect it from the weather.

\Vith this construction, should an insulator be broken, a new one can be secured in place with the same rubbers and screw that secured the old one, so that the line-repairer will only have to carry a small key and a number of insulators, no nails, hammer, screwdriver, screws, &c., being necessary.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- Au insulator l'or telegraplrwires, formed of the insulator A, made of glass, porcelain, or glazed brown ware, perforated longitudinally and countersunk at the lower end of the perforation, the screw B, made with a round head having a square hole formed in it, the rubber bands D, and the rubber rings E F, substantially as herein shown and described.

JOHN HENRY BLOOBIFIELD.

\Vitnesses ERLE S. TALFORT, J. Ponncnn. 

